#include "apue.h"
#include <pthread.h>

struct foo {
    int a, b, c, d;
};

void printfoo(const char *s, const struct foo *fp) {
    printf("%s", s);
    printf(" structure at 0x%lx\n", (unsigned long)fp);
    printf(" foo.a = %d\n", fp->a);
    printf(" foo.b = %d\n", fp->b);
    printf(" foo.c = %d\n", fp->c);
    printf(" foo.d = %d\n", fp->d);
}

void *thr_fn1(void *arg) {
    struct foo *foo;
    foo= malloc(sizeof(struct foo));
    foo->a= 1;
    foo->b= 2;
    foo->c= 3;
    foo->d= 4;
    printfoo("thread 1:\n", foo); 
    pthread_exit((void *)foo);
}

void * thr_fn2(void *arg){
    printf("thread 2: ID is %lu\n", (unsigned long)pthread_self());
    pthread_exit((void *)0);
}

int main(void) {
    int err;
    pthread_t tid1, tid2;
    struct foo *fp;
    if ((err= pthread_create(&tid1, NULL, thr_fn1, NULL)))
        err_exit(err, "can't create thread 1");
    if ((err= pthread_join(tid1, (void *)&fp)))
        err_exit(err, "can't join with thread 1");
    sleep(1);
    printf("parent starting second thread\n");
    if ((err= pthread_create(&tid2, NULL, thr_fn2, NULL)))
        err_exit(err, "can't create thread 2");
    sleep(1);
    printfoo("parent:\n", fp);
    free(fp);
    exit(0);

}
